Background: This study compared the 16-item Clinician and Self-Report versions of the Quick Inventory of Depressive Symptomatology (QIDS-C16 and QIDS-SR16) and the 10-item Montgomery-Asberg Depression Rating Scale (MADRS) in adult outpatients. The comparison was based on psychometric features and their performance in identifying those in a major depressive episode as defined by the Mini-International Neuropsychiatric Interview for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition.
Methods: Of 278 consecutive outpatients, 181 were depressed. Classical test theory, factor analysis, and item response theory were used to evaluate the psychometric features and receiver operating characteristic (ROC) analyses.
Results: All three measures were unidimensional. All had acceptable reliability (coefficient a=.87 for MADRS10, .82 for QIDS-C16, and .80 for QIDS-SR16). Test information function was higher for the MADRS (ie, it was most sensitive to individual differences in levels of depression). The MADRS and QIDS-C16 slightly but consistently outperformed the QIDS-SR16 in differentiating between depressed versus nondepressed patients.
Conclusion: All three measures have satisfactory psychometric properties and are valid screening tools for a major depressive episode.